1. Field of the Invention
The present invention relates to computer systems, methods, and products for analyzing images and, more particularly, for aligning grids on scanned images of high-density arrays of biological materials and analyzing pixilated information within individual grid elements.
2. Related Art
Spotted arrays, such as those made using the Affymetrix® 417™ or 427™ Arrayer from Affymetrix, Inc. of Santa Clara, Calif., are widely used to generate information about biological systems. Also, synthesized probe arrays, such as Affymetrix® GeneChip® arrays, have been used to generate unprecedented amounts of information about biological systems. For example, the GeneChip® Human Genome U133 Set (HG-U133A and HG-U133B) is made up of two microarrays containing over 1,000,000 unique oligonucleotide features covering more than 39,000 transcript variants that represent more than 33,000 human genes. Experimenters can quickly design follow-on experiments with respect to genes, EST's, or other biological materials of interest by, for example, producing in their own laboratories microscope slides containing dense arrays of probes using the Affymetrix® 417™ or 427™ Arrayer, or other spotting device.
Analysis of data from experiments with synthesized and/or spotted probe arrays may lead to the development of new drugs and new diagnostic tools. In some applications, this analysis begins with the capture of fluorescent signals indicating hybridization of labeled target samples with probes on synthesized or spotted probe arrays. The devices used to capture these signals often are referred to as scanners, an example of which is the Affymetrix® 428™ Scanner.
There is a great demand in the art for methods for organizing, accessing and analyzing the vast amount of information collected by scanning microarrays. Computer-based systems and methods have been developed to assist a user to obtain, analyze, and visualize the vast amounts of information generated by the scanners. These commercial and academic software applications typically provide such information as intensities of hybridization reactions or comparisons of hybridization reactions. This information may be displayed to a user in graphical form. In particular, data representing detected emissions conventionally are stored in a memory device of a computer for processing. The processed images may be presented to a user on a video monitor or other device, and/or operated upon by various data processing products or systems. Techniques are known for identifying the data representing detected emissions and separating them from background information. For example, U.S. Pat. No. 6,090,555 to Fiekowsky, et al., which is hereby incorporated by reference herein in its entirety for all purposes, describes various of these techniques.